9. In revisiting Case Study 6.2, we computed a confidence interval for the difference in mean DHEA-S levels for 45- to 49-year-old women meditators and nonmeditators and concluded that there probably was a real difference in the population means because most of the interval was above zero. Now we will compute results for the two groups separately and compare them.

a. Compute a 95% confidence interval for the mean DHEA-S level for 45- to 49-year-old women in the comparison group.

b. Compute a 95% confidence interval for the mean DHEA-S level for 45- to 49-year-old women in the TM group.

c. Based on the intervals computed in parts a and

b, would you conclude that there is a difference in population means between the comparison and TM groups? Explain.